Story arcs
Story arcs are stories in Star Trek that are told over the course of multiple episodes. They are not simply two-parters or recurring characters and themes, but rather plots that are interwoven with other arcs and plot threads. The most famous example is DS9's introduction of the Dominion and the eventual Dominion War. Story arcs often take precedence over other plot elements and consume a series for several consecutive episodes, but in many cases (such as the Dominion War) they may take a back seat and re-enter the picture later on. Prior to DS9, story arcs were a relatively minor part of the Star Trek universe. TOS and TNG both largely restored the status quo ante at the end of each episode, and even two-part episodes were somewhat rare. This changed due to the stationary nature of space station Deep Space 9, which did not simply move on to the next adventure each week; characters' actions had lasting consequences, and the events of one episode directly influenced the next. VOY took the idea of the story arc in a different direction by setting itself aboard a starship as per the traditional Trek formula but stranding its crew in the distant Delta Quadrant. This both enhanced and reduced the prevalence of story arcs; while alien races such as the Kazon and Borg apppeared in multiple episodes, the show was hampered by its very nature: the object was to leave familiar elements behind, which meant each plot thread had a limited life span. Feature Length Episodes These episodes are originally broadcast in two hours, as opposed to the standard one hour. After their original run, feature length episodes are re-cut as two part episodes (see below). They include: *TNG **Encounter at Farpoint **All Good Things... *DS9 **Emissary **The Way of the Warrior **What You Leave Behind *VOY **Caretaker **Dark Frontier **Flesh and Blood **Endgame *ENT: Broken Bow Two-Part Episodes These episodes air seperatly, but tell the same story. It is typical for the first part to end with the line "To Be Continued...". They are frequently used to end and begin seasons. Two-Part episodes include: *TOS: The Menagerie, Part I & The Menagerie, Part II *TNG **The Best of Both Worlds, Part I & The Best of Both Worlds, Part II **Redemption, Part I & Redemption, Part II **Unification, Part I & Unification, Part II **Time's Arrow, Part I & Time's Arrow, Part II **Chain of Command, Part I & Chain of Command, Part II **Birthright, Part I & Birthright, Part II **Descent, Part I & Descent, Part II **Gambit, Part I & Gambit, Part II *DS9 **The Maquis, Part I & The Maquis, Part II **The Search, Part I & The Search, Part II **Past Tense, Part I & Past Tense, Part II **Improbable Cause & The Die is Cast **Homefront & Paradise Lost **Image in the Sand & Shadows and Symbols *VOY **Basics, Part I & Basics, Part II **Future's End, Part I & Future's End, Part II **Scorpion, Part I & Scorpion, Part II **Year of Hell, Part I & Year of Hell, Part II **The Killing Game, Part I & The Killing Game, Part II **Equinox, Part I & Equinox, Part II **Unimatrix Zero, Part I & Unimatrix Zero, Part II **Workforce, Part I & Workforce, Part II *ENT **Shockwave, Part I & Shockwave, Part II **Storm Front & Storm Front, Part II **Affliction & Divergence **In a Mirror, Darkly & In a Mirror, Darkly, Part II **Demons & Terra Prime Three-Part Episodes *DS9: The Circle, The Homecoming, and The Siege *ENT **Borderland, Cold Station 12, and The Augments **The Forge, Awakening, and Kir'Shara **Babel One, United, and The Aenar Multi-Episode Arcs *DS9 **The Beginning of the Dominion War ***Call to Arms ***A Time to Stand ***Rocks and Shoals ***Sons and Daughters ***Behind the Lines ***Favor the Bold ***Sacrifice of Angels **The Ending of the Dominion War ***Penumbra ***Til Death Do Us Part ***Strange Bedfellows ***The Changing Face of Evil ***When It Rains... ***Tacking Into the Wind ***Extreme Measures ***The Dogs of War ***What You Leave Behind (feature-length) *ENT **Search for the Xindi superweapon Non-Consecutive Arcs *The Talosians **The Cage **The Menagerie, Part I **The Menagerie, Part II *Harry Mudd **TOS: "Mudd's Women", "I, Mudd", & TAS: "Mudd's Passion" *Khan Noonien Singh **TOS: "Space Seed" & Star Trek II: The Wrath of Khan *Tribbles **TOS: "The Trouble with Tribbles, TAS: "More Tribbles, More Troubles", & DS9: "Trials and Tribble-ations" *Eddington v. Sisko **DS9: "For the Cause", "For the Uniform", & "Blaze of Glory" Mirror Universe Episodes see also Mirror Universe * ENT: ** "In a Mirror, Darkly" ** "In a Mirror, Darkly, Part II" * TOS: ** "Mirror, Mirror" ** "The Tholian Web" (related to In a Mirror Darkly, Part I and II) * DS9: ** "Crossover" ** "Through the Looking Glass" ** "Shattered Mirror" ** "Resurrection" ** "The Emperor's New Cloak"